Optimal bandwidth expansion for DS/SSMA communication over a multipath Rayleigh fading channel

Abstract

We consider a convolutionally coded asynchronous direct-sequence spread-spectrum multiple access (DS/SSMA) communication system employing an ideal RAKE receiver over a multipath Rayleigh fading channel. Both spread spectrum and channel coding have the effect of mitigating the multiuser interference and expanding the channel bandwidth. The optimum bandwidth expansion in maximizing the normalised throughput is investigated in connection with the number of users and the decoder complexity. The required channel bandwidth reduction via soft decision decoding is also examined.<>